Using nanotechnology, Italian and German researchers have succeeded in locating red blood cells in the wounds a 5,000-year-old iceman mummy.

Samples from a 5,000-year-old mummy’s stomach and intestines have allowed scientists to reconstruct his very last meal, and his DNA has been decoded. The conditions surrounding his violent death appear to have been clarified. However, what had, at least up to now, eluded the scientists, was finding any traces of blood in Ötzi, the 5,000-year-old glacier mummy.

Examination of his aorta had yielded no results. Yet recently, a team of scientists from Italy and Germany, employing nanotechnology, succeeded in locating red blood cells in Ötzi’s wounds, thereby discovering the oldest traces of blood to have been found anywhere in the world.

“Up to now there had been uncertainty about how long blood could survive--let alone what human blood cells from the Chalcolithic period, the Copper Stone Age, might look like,” Dr. Albert Zink, head of the Institute for Mummies and the Iceman at the European Academy, Bozen-Bolzano (EURAC), explained the beginning of the study that he conducted with Drs. Marek Janko and Robert Stark, materials scientists at the Center of Smart Interfaces at Darmstadt Technical University (Germany). Even in the latest forensic technologye it has so far been almost impossible to determine how long a trace of blood had been present at a crime scene. Scientists Drs. Albert Zink, Marek Janko, and Robert Stark are assured that the nanotechnologic technology that they utilized out on Ötzi’s blood to analyze the microstructure of blood cells and miniscule blood clots might possibly lead to a break-through in this field.

The investigators used an atomic force microscope to examine thin tissue sections from the wound where the arrow entered Ötzi’s back and from the laceration on his right hand. This nanotechnology instrument scans the surface of the tissue sections using a very fine probe. As the probe moves over the surface, sensors measure every miniscule deflection of the probe, point by point and line by line, building up a three-dimensional (3D) image of the surface. What emerged was an image of red blood cells with the classic “doughnut shape,” precisely as is found in healthy people today.

“To be absolutely sure that we were not dealing with pollen, bacteria, or even a negative imprint of a blood cell, but indeed with actual blood cells, we used a second analytical method, the so-called Raman spectroscopy method,” reported Drs. Janko and Stark, who, with Dr. Zink, are also members of the Center for NanoSciences (Munich, Germany). In Raman spectroscopy, the tissue sample is lit by a laser beam and analysis of the spectrum of the scattered light allows the user to identify various molecules. According to the scientists, the images resulting from this process corresponded to present-day samples of human blood.
While examining the wound at the point where the arrow entered the body, scientists also identified fibrin, a protein involved in the clotting of blood. “Because fibrin is present in fresh wounds and then degrades, the theory that Ötzi died some days after he had been injured by the arrow, as had once been mooted, can no longer be upheld,” explained Dr. Albert Zink.

The scientists published their research findings online before print May 2, 2012, in the Journal of the Royal Society Interface.